Constant velocity universal joint



A. Y DODGE CONSTANT VELOCITY UNIVERSAL JOIN'' July 4, 1944.

Filed Feb. s, 1940 2 sheets-siegt 1 No. bm. QN bh. uw N Nl Q July 4,1944- A. Y.Y DODGE f 2,352,776

CONSTANT VELOGITYZUNIVERSAL JoiNT Filed Feb.'3, 1940 2 Sheets-Shea?I 2 raten-ted .my 4, 1944 y CONSTANT VELOCITY UNIVERSAL JOINT Adiel Y. Dodge, Rockford, Ill., assigner to Borg- Warner Corporation, Chicago, Ill., a corporation of lIllinois Application February 3, 1940, Serial No. 317,044

Claims.

This invention relates to universal joints, and has as its general object to provide a relatively inexpensive constant velocity joint of the type employing, as the intermediate torque transmitting means, a series of bearing balls engaged in recesses in the respective terminal members which, in this type of joint, are customarily in the form of male and female members. In most of the constant velocity joints previously devised, the ball recesses are arcuate in longitudinal contour, on radii struck froml the center ofthe joint. But such recesses are dilicult and expensive to machine, and a primary object of the present invention is to eliminate the necessity for such expensive machining. To thisend,

the invention contemplates a joint wherein the recesses are straight and parallel to the axes of their respective terminal members, and wherein the female terminal member is in the form of a stamped sheet metal shell having recesses thev inner surfaces 0f which are iinished by a coining operation.

In order to achieve the constant velocity characteristic, it is necessary to control the movement of the torque -transmitting balls so that they are positioned at all times in a plane bisecting the angle defined between the axes 'of 'the respective terminal members, and the present invention aims to substantially achieve this condition. It is possible to accomplish this by sev-V f cesses will assume converging-diverging relationships. If a ball is allowed `to move too far in the direction of the converging end of its respective recesses.' it will become wedged between the recesses, and if it is allowed to move too farin the other direction, it will lose its bottoming contact with the recess of the male member. The invention has as another object to provide a joint wherein the balls will be maintained at all times in bottoming contact with both sets of recesses so as to maintain a tight torque transmitting connection and avoid lost motion.

'I he invention further contemplates the ern-` vthe constant bottoming characteristic.

ployment of single means, in the form of a cage and piloting mechanism, for positively controlling the movement of the balls so as to achieve both the constant velocity characteristic and I have discovered that it is possible, in a joint employing straight ball recesses, to maintain the balls substantially in the plane of the bisector, and at the same time to maintain them in constantly bottoming relation to their respective recesses, by employing arcage and piloting mechanism.

Another object of the invention is to provide a novel and improved piloting mechanism.

A further object of the invention is to provide a vconstant velocity universal joint which is adapted, in addition to its normal function of transmitting torque.' to take up axial shifting of the terminal members relative to each other,

thereby eliminating the necessity for a slip joint l Fig. 2 is a transverse sectional view of the samel taken as indicated by the line 2-2 of Fig. l;

Fig. 3 is a, longitudinal sectional view of a universal joint embodying a somewhat modied form of the invention.

As an example of one form in which the invention may be embodied, I have shown in Figs. 'l and 2 a universal joint comprising, in general, a male terminal member I0, a female terminal member or shell II, an annular series of torque transmitting balls I2, a cage I 3 in which` the balls are imprisoned, and piloting mechanism I4 for determining the position of the cage I3.

The male member I0 may be formed on or secured to the forward end of a propeller shaft I5 Yof an automotive vehicle. The shell Il would in that case4 be attached to the rear endof the tail shaft I6 of the vehicle transmission.

In accordance with the invention, the female member I I comprises a sheet metal shell portion I1 in the shape of 'a uted cylinder, and a hub portion I 8 having a flange I9 to which the shell I1 is secured by means of a'fiange 2| formed on its one end, and a series of screws 2'0 extended through the ilange 2| and threaded into the fiange I9. The ange 2| is provided with a machined internal locating shoulder 22 adapted to snugly receive an external shoulder 23 machined on the flange I9.

The iiuted portions 24 of the shell I1 have semi-cylindrical interior surfaces forming the rel cesses 25 in which the torque transmitting balls I2I are received. These surfaces are rapidly and inexpensively finished to smooth and accurate contour by a coining operation. Since the recesses 25 are straight, it is possible to form the shell I1 of sheet metal by a deep drawing or other suitable die forming operation. The end of the sleeve opposite the flange 2| is formed inwardly to provide a toroidal groove 26 adapted to receive and secure one end of a flexible lubricating retaining boot 21. The other end of the boot 21 may be secured in constricting engagement with a toroidal groove 28 in the shoulder 29 of the male member I0.

The hub I8 maybe internally splined to receive the splined end 30 of the tail shaft I6, and adapted to be secured thereon by means of a nut 3| threaded on a reduced end portion 32 of the tail shaft and engaging, through the medium of a washer 33, a shoulder 34 formed in the hub I8.

The male member I is formed at its end with a head 35 provided with recesses 36 in which the inner regions of the balls I2 are received. 'I'he lateral surfaces 31 of the head 35 between the recesses 36 are spherical and are snugly received within the spherical ball cage I3. The recesses 36 are straight, semi-circular in cross-section, and parallel to the axis of the male member I0. When the axes of the mem-bers I0 and II are aligned, as in Fig. 3, the recesses 25 and 36 will be equidistant from each other at all points along their common axial extent. As these axes become inclined relative to each other as shown in Fig. l, the recesses 36 will assume a converging-diverging relationship, the converging ends of the recesses moving closer together than formerly, and the opposite ends moving farther apart.

This relationship of the recesses becomes important in maintaining, snug bottoming contact of the balls I2 in the respective recesses when the terminal members are inclined as shown in Fig; 1. If the recesses 36 were arcuate and concentric with the axis of the joint at 39, any movement of the balls out of a plane perpendicular to the axis of the shell I1, would result in separation from the recesses 36 (it being assumed that the parts are rotating so that centrifugal force would be effective t0 maintain the balls in bottoming engagement with the recesses 25) but with the converging relationship of the recesses, it is possible to maintain bottoming of the balls in both sets -of recesses, by'shifting the balls with reference to the recesses 36 toward the converging ends of the recesses. shifting of the balls, with reference to the recesses 25, toward the diverging ends of the recesses.

The shifting toward the converging ends of the recesses 36 is so proportioned to the shifting toward the diverging ends of-the recesses 25 that the plane of the balls will be maintained in positions at all times substantially bisecting the axes of the respective terminal members. I have discovered that it is possible to thus maintain the plane of the balls in the bisector `of the angle of the terminal members, and at the same time to maintain the Ibottoming of the balls inboth sets of recesses. In accordance with known principles,

` pivotal movement of the joints. `But the main- Such shifting is compensated for by tenance of this center 39 is in turn dependentv upon the maintenance of the balls I2 in a plane intersecting the desired center 33. This is made possible by the employment of the cage I 3 andthe piloting mechanism I4 which will now be described.

The cage I3 terminates at one end in a cylindrical sleeve 4I'. Axlally slidable in the sleeve 4I is a Ibushing 42 having a spherical interior bearing surface socketing a ball 43 formed on one end of a pilot nger 44. At the other end of the finger 44 is a spherical head 45 which is received in a semi-spherical socket 46 formed in a plate 41 received in a bore 43 of the hub I8 and abutted against a shoulder 49.

A push rod 5I), slidable in a bore 5| in the end of the male member II), under the pressure of a spring 52 compressed between the end of the push rod 5|) and the end of the bore 5|, has its spherical head 52 urged into engagement with a semi-,- spherical socket 54 in the end of the ball 43, so as to maintain the head'45 of the finger .44 constantly bottomed in the socket 46. As the axes o! the terminal members become inclined, the finger 44, and with it the Abushing 42, will be moved away from the end of the male member, the bushing 42 sliding in the collar 4I.

The position of the cage I3 will shift in accordance with the shifting of the center of the ball 43. The center of the ball 43 swings in an arc centered at the head .45. 'I'he angle subtended between the center of the head 53 and the axis of the sleeve I1, as indicated at A of Fig. 1,' may be taken as the angle of inclination of the terminal members. 'Ihe angle B subtended between the center of the ball .43 and the axis of the shell I1 will Ibe less than the angle A. The distances between the center 39 and the centers of the balls 45, 43,Aand 53, is so proportioned that within the normal operating range of the joint the angle B will be approximately half that of the angle A and, accordingly, the plane of the balls I2 will substantially bisect the angle between the terminal members.

A The form of the invention shown in Fig. l is suitable for use in connection with the .so-calledl torque tube type of vehicle drive, wherein the rear end of the propeller tube I5 is axially fixed with reference to the frame of the vehicle by means of a wish-bone shaped bracing member-.

The tail shaft I6 being also substantially xed with reference to the chassis, not only against axial movement but against lateral movement as well, the position of the center 39 will be determined by the lrear end of the propeller shaft I5. Any axial shifting of the center 3,3 occasioned by vertical movement of the rear end of the shaft I5 relative to the vehicle chassis (under conditions wherein the center of swinging movement of the brace member above referred to does not coincide with the center 39) will be taken up by shifting of the push rod 50 under or against the compression of the spring 52, and correspond.- ing shifting of the bushing 42 in the collar 4|.

Inthe form of the invention shown in Fig. 3, the compression spring 52a is located at the opposite end of the finger 44, being received in a bore 5t in the tail shaft iaand engaged againstv a @eating socket member 56 which isA axially slidable in a bore 51 inthe plate member 49a, Inl stead of the axially slidable push rod 50, I provide a stud 50a fixed in the boe Sla of the'male il member I0, and having a spherical head 53a engaged in the socket 5I of the ball 43. lllhe ball 53a, may be formed vintegrally with the male member l0. This form of the invention is parexternal recesses registering with said internal ticularly suitable for accommodating a considerl0 able amount ofaxial shifting of the male member l0 with reference to the shell I1, without destroying the desired relationship between the center 39 and `the centers of the balls 53a, I3 and 45,

respectively. Accordingly, it is suitable for eml5 ployment in connection with the Hotchkiss type of drive wherein the rear end of the propeller A shaft I0 is iloat-ingly arranged with reference to the chassis. Thus, the joint may constitute not torque, but also a slip joint for compensating axial'shifting between thetail shaft and the propeller shaft. Such slip joints are commonly employedv in the form of separate joints. By combining the functionsof the slip joint with the normal functions of a universal joint, considerable saving in expense is eil'ected. This feature is embodied to some extent in the form of the invention shown in Fig. 1, although where considerable axial take .up is desired, the form shown 3 in Fig. 3 is preferable.

While I have described my invention in connection with one specific embodiment thereof, it

is to be understood that this is byway of i1lus-' tration and not'by' way of limitation, and the 35' scopeof my inventionv is defined solely by`the appended claims which should be construed as broadly as the prior art will permit.

I claim: v

1.In a universal joint, afemale member hav- 40' ing internal recesses, a male terminal member lonly a constant velocity means for transmitting zo recesses, torque transmitting ,balls engaged ing.-

said recesses for establishing driving connection between said members, a spherical cage in which said head is socketed, and in which said balls are imprisoned, said cage having a cylindrical collar, a bushing axially slidable in said collar, a piloting linger having one end socketed in said bushing and its other end in pivotal association with said female member, and a spring pressed plunger axially slidable in said male member and having at its outer end a socketing connection with the socketedA end of said linger.

4. In a universal joint, a female member having internal recesses, a male terminal member having at its end a spherical head provided with external recesses-registering with said internal u, recesses, torque transmitting balls engaged in said recessesvfor establishing drivingA connection between said members, a spherical cage in which said head4 is socketed, and in which said balls are imprisoned, said cage having a collar, a bushing axially'slidable in said collar and formed internally with a spherical bearing socket, a piloting finger havingv one end portion pivotally received in said bushing socket, means placing the other end of said pilot finger in pivotal association with said female member, and means establishing a pivotal connection between saidk male terminal member and said lone end portion of the piloting finger, said last means including a spherical head carried by and protruding from the end of said male member, said piloting nger being provided'in said one end portion with a recessed bearing socket, said spherical head protruding from said male member being received said bearing socket.

5. In a universal vjoint, a female member having internal recesses, a male terminal member having at its end a spherical head provided with a external recesses registering` with said internal internal spherical bearing surface, a piloting n- 50 ger having one end socketed in said bushing and its other yend in pivotal association with said female member, and a spring'pressed plunger' axially slidable in said male member and having at its outer end va socketing connection with 5 the sockete'd end of said finger.

2. In a universal joint, a female member hav- 'ing internalrecesses, amale member having at its end aspherical head-provided with external recesses registering with said internalvrecesses, a

between said members, a spherical cage in which said head is socketed and in which Vsaid balls are' imprisoned, piloting means for said spherical plurality of torque transmittingballs engaged in "w said recesses for establishing ardrivingl connection between said members, a spherical cage in which said head is socketed and in which said 'balls are imprisoned, said cage having, opposite the end of said male member a collar, a bushing' 65 axially slidable in said collar, apiloting linger having one end socketed for universal movement in said bushing, a socket element axially slidagile in said female'member, the` other end of cage comprising a tubular collar protruding from said cage, a bushing axially slidable in said collar, said bushing being formed internally to define a spherical-like bearing socket, a piloting.

linger-like member having a first spherical portion received in said bushing socket, a recessed Y spherical socket formed in a .first end portion of said ,linger member, a spherical -protuberance extending axially from saidv male `member and received in said pilot nnger socket, said pilot linger being provided with a second spherical portion spaced from said first spherical portion, means for pivotally associating said second spherical portion with said female member, and

said ringer being socketed therein, a spring ar- 7 ranged to exert pressure against said socketmember so as to maintain the same in engage.

means including a compression spring for transmitting a generally axial force to said pilot fingerlike member and said spherical protuberance extending i'rom said male member. 

